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SPEAKER 1: Welcome, everyone.

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My name is Carter.

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And today I'm going to show
you my guessing game and how

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I can use debug50 to help
figure out what's wrong with it.

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So here, I'm trying to
write a guessing game that

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is written in the spirit of
the elementary school game

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where you would guess a number
and someone would tell you,

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it's right or wrong.

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And I called my program Guess.

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So I can run it in the
terminal with ./guess.

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Here go to ./guess, hit Enter,
and I have to guess a number.

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So here I might guess,
maybe 2, and hit Enter.

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But then I get this flood
of messages in the terminal.

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And I'm wondering, well,
what's wrong with this?

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Why am I getting so many messages here?

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And to try to figure that out, I can
go into my code with code guest.c.

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And then I can see, well, I'm not
entirely sure what may be wrong here.

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So I need to pause my
code at some point.

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And for that, I can use a break point.

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So let me go ahead and go to this
left side of my guess.c file, where

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I see these red circles pop up.

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I can click on one of them
to turn it bright red.

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And at that point, I've set
a pause point in my code.

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And I can use debug50 to go in
and actually step through my code

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and see what's going on in there.

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So let me go ahead and type
debug50 of guess, hit Enter.

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So now that I have my
code opened up in debug50,

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I can see a few different things.

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I can see that my number
variable is currently set to 0.

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And my guess is currently
set to this odd 32,764.

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But as I go through
my code, I'll actually

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see those numbers fall into place.

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So if I use this Step Over button to
walked to the next line of my code,

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I can see that number becomes
5, as I expect it to on line 6.

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And then as I go to line 8 and
Step Over that, I get prompted for,

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what's my guess?

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And at that point, I
might type, well, 3 again.

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And I'll hit Enter.

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And then I see guess becomes 3.

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So now I'm wondering, well, if my
guess is wrong and my number is 5,

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my guess is 3, shouldn't I
only get wrong guess just once?

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So I'll actually just keep walking
through my code with Step Over.

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And I'll see, I'm printing "Wrong
guess!", which seems right.

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And now I should just exit the program.

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That should be it.

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But I really see that my
line in that yellow highlight

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is going back up to 10, line 10 there.

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And it's actually continuing to go
through and print "Wrong guess!"

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And so at this point, I can actually
see that maybe the bug in my code

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is I shouldn't have used a while loop.

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I should have, maybe,
used an if statement,

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where I'm only checking
for this condition once.

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So now that my while loop has
changed to an if statement,

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I should be able to recompile
my code and see what's changed.

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So I can use "make guess".

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And then I'll run my code, guess.

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And when I guess 3, I guess
I should get "Wrong guess!"

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So I'll do 3.

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And then I'll get "Wrong guess!",
but also "You're correct!".

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And at this point, there's
probably another bug in my code.

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And so I'll actually
leave this one up to you,

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to use debug50 and see, well, why
am I getting both "Wrong Guess!"

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and "You're correct!"?

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